Looper for sewing-machines.



Patented Nov. 26, 190]! W. M. AMMERMAN.

LOOPEB FOB SEWING MAGHiNES.

(Application filed Feb. 12. 1901.)

(No Modal.)

2 Sheets-Sheet I.

WITNESSES:

INVENTQR ATTORNEY 7 Patented Nov. 26, I901. W. M. AMMERMAN;

LOOPEB FOB SEWING MACHINES.

. (Application filed Feb. 12. 1901.) I (No Mode!.) 2 Sheets-Sheet 2."

WITNESSES: INVENTOR ii. gm. BY

ATTORNEY UNITED STATES PATENT OFF CE.

WILLIAM M. AMMERMAN, OF NEW HAVEN, CONNECTICUT, ASSIGNOR TO EDWIN J. TOOF, OF NEW HAVEN, CONNECTICUT.

LOOPER FOR SEWING-MACHINES.

SPECIFIOATZ'ON formingpart of Letters Patent N 0. 687,511, dated November 26, 1901,

ilpplication filed February 12, 1901. Serial No. 46,966. (No model.)

To all whom it may concern.-

Be it known that 1, WILLIAM M. AMMER- MAN, a citizen of the United States, and a resident of the city and county of New Haven, State of Connecticut, have invented certain new and useful Improvements in Sewing-Machine Loopers, of which the following is a specification, reference being had to the accompanying drawings, forming part thereof.

My invention relates to that class of loopers or loop-spreaders disclosed in Letters Patent No. 629,735, dated July 25, 1899, and No. 514,653, dated February 13,1894, which are adapted for detachable connection tothe ordinary rotary shuttle of a lock-stitch sewingmachine, so that by removing the usual bobbin-case and bobbin from the shuttle and inserting the looper the machine may be thereby changed from a lock-stitch to a chain-stitch machine, or vice versa, without other trouble than would be required to remove and insert the ordinary bobbin-case and bobbin. The looper as disclosed in said patents, being termed in one looper and in the other loop-spreader,

comprises a suitable attaching shank or body having a forked tail, which latter operates to receive the needle-thread loop on its under side after being released by the beak of the shuttle and hold the same in an open position across the path of the needle until the latter at its next descent passes another loop through the same, after which the looper releases the first loop, which is tightened as the succeeding loop, drawn through the first loop, is distended.

In the particular construction of looper shown in Patent No. 514,653 one prong of the up, so that it will only be engaged by the rear or long prong, in which event the thread-loop will not be opened or distended across the path of the needle and the next stitch will consequently be skipped or missed. To avoid possibility of stitches being skipped in such manner has been one of the principal objects of my present invention, which object I socure by providing the looper with means for engaging the needle-thread loop as it is released by the beak of the shuttle and controlling the same when being drawn up by the take-up so as to prevent twisting or undue slack therein, whereby the loop will be caused to pass in its proper position under both prongs of the looper, after which the loop is released by its said engaging means.

A further object of my present invention is to provide an improved locking device for the loo'per that may be readily and conveniently operated to release the latter from connection with the shuttle and permit its removal therefrom. This object I secure as follows: The looper is provided with a central stem, which the operator grasps between the thumb and finger when taking hold of the looper for the purpose of placing the same in connection with the shuttle or removing it therefrom, and in accordance with myinvention I arrange a locking-lever with its operating end in such relation to this stem that as the operator takes hold of the latter, as mentioned, the back or nail of the finger engages said locking-lever, and thereby moves it to a position to permit of the removal of the looper from the shuttle or its connection therewith.

Referring to the accompanying drawings, Figures 1, 2, 3, 4, and 5 are front'views of a Standard rotary shuttle with my improved looper connected thereto and a portion of the cloth-plate and needle, showing the operation of the looper at different times during the formation of a stitch. 'Fig. 6 is an enlarged section through the shuttle and attached looper. Fig. 7 is a View similar to that of Fig. 6, showing the looper disconnected from the shuttle and the locking-lever in its releasing position, as held by the finger of the operator; and Fig. 8 is a front view of the looper removed from the shuttle.

In said drawings, 1 indicates the body of an ordinary Standard rotary shuttle, having at its periphery a point or beak 2 for seizing the loops of needle-thread and also having a central recess 3 for the reception of the bobbin-case and bobbin. At the center of the recess 3 is the usual bobbin-supporting stud 4.

5 indicates the looper, the same in the present instance shown being substantially the same in certain of its general features of construction as that disclosed in said Patent No. 514,653, and consists of a forked tail, one prong 6 of which is short and terminates some distance in advance of the beak of the shuttle and the other prong 7 of which is of sufficient length to extend slightly past the said beak and is curved or deflected to one side, so as to leave a'clear thread-passage between the same and said beak. Between the said two prongs is a space 8 for the passage of the needle.

The looper 5 is preferably formed integral with a supporting shank or body 9, which is adapted to be seated in the shuttle and is provided with a central perforation 10 to receive the stud 4 therethrough. A hollow post 11 is rigidly secured on the front side of the body 9, with its opening registering with the said opening in the latter, so as to fit over the stud 4 when the looper is connected to the shuttle, as shown in Fig. 6. This hollow post 11, in accordance with my invention, is provided with a cam-surface 12 at its outer end, which projects beyond the end of the stud 4 and the outer face of: the shuttle, so as to engage with the front side of the needlethread loop as, it is moved across the face of the shuttle and, control the same in a manner as will be described. The particular form of this cam-surface, as herein shown, is that of a shoulder 13, which extends outwardly from the end face of the post at quite an abrupt 4o, angle and then tapers backwardly in a return curve toward the inner end of the shoulder, as clearly shown in Fig. 6.

The operationof so much of the invention as described is as follows: The usual bobbincase and bobbin being removed from. the shuttle and my improved looper connected therewith the machine is set in motion so as to rotate the shuttle and connected looper and reciprocate the needle in the usual manner. Then as the needle descends and rises it throws out a loop of thread, which is seized by the beak of the shuttle, and as the latter continues its rotation and the needle continues to rise the said loop is carried around the shuttle in the usual manner until it reaches a position to be released or cast off by the beak of the shuttle, as shown in Fig. 1, at which time the shoulder 13 at the end of the looper-post has reached a position to engage with the front side of the loop, as shown. As the loop is new cast off by the beak of the shuttle and drawn up by the take-up the engagement of the looper-shoulder 13 with the front side of the loop causes the thread to be drawn or guided around the same, so as to control the slack in the thread and insure its passing beneath the two prongs of the looper, as shown inFig. 2. The threadloop now continues to be retained and guided by the shoulder 13 until the slack in the rear side of the same is taken up, as shown in Fig. 3, after which the loop is cast off by the said shoulder or projection 13, the tapering surface at the rear of the latter being so formed (see Fig. 6) that when the thread is drawn upward thereover it acts to draw the loop outward and release the same from engagement with the shoulder 13. The function of the cam 13, as described, is thus twofold. First, it controls the loop so as to insure its passing beneath the two prongs of the looper and being properly engaged by the latter, and, second, in taking up and controlling the slack it prevents untwisting and consequent weakening of the thread. After the loop has been cast ofi by the shoulder 13 and drawn up into engagement with the looper the action of the latter in completing the stitch is substantially the same as in the said prior patents referred to, the same in brief being as follows: When the shuttle is in the position shown in Fig. 4, the loop will be held by the opposite prongs of the looper in an open or distended position across the path of the needle, at which time the latter will descend into the space between the prongs and carry its thread through the said distended loop. As the shuttle continues its rotation the first loop passes onto the long prong 7, as shown "in Fig. 5, and the beak of the shuttle now seizes a second loop thrown out by the needle as it rises, which second loop is drawn through the first loop as it is expanded, and the said first loop is cast off from the prong 7 and is tightened in the work in the usual manner.

As a means for removably securing the looper in connection with the shuttle I have I connected a locking-lever 15 to the body 9 of thelooper on a pivot 16,arranged transversely ,to the looperpost, one end of which lever when in looking position is adapted to engage with the inner wall of the shuttle, as at 17 in Fig. 6, a spring 18 acting on said lever to normally hold the same in its locking position. The operating end 19 of the lever 15 extends into a position adjacent to the outer end of the post 11 and at an angle thereto whereby it will be operated as follows: When the looper is to be'removed from or connected with the shuttle, the operator grasps the end of the post 11 between the thumb and finger, as indicated by dotted lines in Fig. 7, and in thus grasping the post the end of the finger is entered between the post and the operating end of the lever, and thereby operates the latter against the pressureof the spring to move its opposite end awayfromlockingpositionrelativetotheshuttle and hold the same in such position, as indicated in Fig. 7, whereby the looper may be readily removed from the shuttle or placed in connection therewith. In order that the eetgsi i post 11 may be more firmly held by the operator, I have provided the same with depressions 20 in its opposite sides to receive the ends of the thumb and finger.

As I do not wish to confine myself to aloose shuttle as a loop-taker for carrying and operating in connection with my improved looper, I will employ the term loop-taker in certain of the claims to designate the shuttle or an equivalent device.

Having thus set forth my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. A loop-taker provided with a forked tail or looper for receiving the thread-loop in engagement therewith after being released or cast off by the. loop taker beak, and with means for engaging said loop and controlling the slack therein intermediate of the time of its release by the loop-taker beak and its engagement by the forked looper, for the purpose set forth.

2. A loop-taker provided with a forked tail or looper for receiving the thread-loop'in engagement therewith after being released or cast off by the loop taker beak, and with means for engaging said loop when released by the loop-taker beak and casting off the same prior to its engagement by the forked looper, for the purpose set forth. I

3. A loop-taker provided with a forked tail or looper for receiving the thread-loop in engagement therewith after being released or cast off by the loop-taker beak, and with a cam for engaging said loop and controlling the slack therein intermediate of the time of its release by the loop-taker beak and its engagement by the forked looper, for the purpose set forth.

4. A loop-taker provided with a forked tail or looper for receiving the thread-loop in engagement therewith after being released or cast oif by the loop-taker beak, one prong of said looper being shorter than the other and terminating in advance of the loop taker beak, and with means for engaging said loop and controlling the slack therein intermediate of the time of its release by the loop taker beak and its engagement by the forked looper, for the purpose set forth.

5. The combination, with a rotary shuttle, of a looper removably connected thereto, said looper being provided with means for receiving the thread-loop in engagement therewith after being released or cast off by the beak of the shuttle, and with means for engaging said loop and controlling the slack therein intermediate of the time of its release by the shuttle-beak and its ehgagemeht the looper,

beak and casting off the same prior to its engagement by the looper, for the purpose set forth.

7. The combination, with a rotary shuttle having the usual central stud, of a looper re movably connected thereto, said looper comprising a forked tail and a connected body portion, the latter being provided with a hollow post fitting over the stud in the shuttle and having means at its outer end for engaging with the thread-loop.

8. A looper,comprisinga supporting-shank provided with a forked tail for receiving a thread-loop in engagement therewith, and with a slack-thread controller arranged to engage with and cast oif the loop prior to its reception by the forked tail, for the purpose set forth.

9. A looper,oomprisinga supporting-shank provided with a forked tail for receiving a thread-loop in engagement therewith, and with a slack-thread-controlling cam arranged to engage with and cast off the loop prior to its reception by the forked tail, for the purpose set forth.

10. A looper, comprising a supportingshank, provided with a forked tail, a slackthread controller, and a locking-lever,for the purpose set forth.

11. The combination,with a rotary shuttle, of a looper removably connected thereto, said looper comprising a forked tail and a connected body portion, the latter being pro- .vided with a post, and a spring-pressed locking -1 ever supported on a pivot arranged transversely to the said post, the said lever having one arm arranged to engage with the shuttle and its other arm arranged with the end thereof extending adjacent to the outer end of the looper-post and in position to be moved to an unlocking position by the operators finger as the latter is placed in holding position on the post.

WILLIAM M. AMMERMAN.

Witnesses:

CHAS. F. DANE, HERBERT E. DANE. 

